This invention relates to a small watercraft and more particularly to an improved fuel injection arrangement for such watercraft.
It is well known that two cycle engines have wide applicability for a number of uses where small size, simple construction and high specific output are desired. A typical example of such applications is as the power plant for a type of water vehicle referred to generally as a "personal watercraft."
Personal watercraft are watercraft that are relatively sporting in nature and that are designed primarily to be operated by a single operator who may carry only a few passengers with him. Frequently, the operator and passenger are seated in straddle fashion and when a plurality of passengers are carried, they sit in tandem. These types of watercraft are quite compact and thus, require compact propulsion systems including the engine.
However, because of environmental concerns and some difficulties in obtaining good exhaust emission control, power sources other than two cycle engines are being considered. However, if the efficiency of a two-cycle engine can be improved by an expedient such as fuel injection, and particularly direct fuel injection, then the replacement with four cycle engines may not be necessary.
Because of the compact nature of these watercraft and particularly their engine compartment and the access thereto, the provision of fuel injection systems presents some problems. This is particularly true with direct fuel injection systems wherein the fuel injector injects directly into the combustion chamber of the engine. Such arrangements position the fuel injector generally in the area of the cylinder head and thus, place it in an area where it may be exposed to damage or water which could deteriorate its performance, particularly if it is electrically operated.
On the other hand, it is desirable if the engine is mounted so that the injector can be easily accessed for service, but this places it is in a position where it may be inadvertently struck or where water may be able to contact it.
It is, therefore, a principal object of this invention to provide a direct cylinder fuel injection engine for use in personal watercraft.
It is a further object of this invention to provide a personal watercraft having a direct cylinder injection system where the injector is readily accessible for servicing but is protected by other components of the engine from damage and water.